With the decrease in the reserves of conventional crude oils, there is increasing use of heavy hydrocarbons such as bitumen extracted from oil sands. These heavy hydrocarbons contain a wide range of materials including usually more than 50 wt. % of material boiling above 525.degree. C., equivalent atmospheric boiling point.
In order to transport these heavy hydrocarbons to a point of use, the bitumen typically is mixed with a diluent such as natural gas condensate to reduce the viscosity of the bitumen for pipelining. Unfortunately, the supply of natural gas condensate may not keep pace with the continuing growth in use of such heavy hydrocarbons.
One technique for eliminating the need for diluent is to thermally process the heavy hydrocarbon in the presence of hydrogen and a catalyst slurry to produce a pipelineable product. In this process, catalyst particles are separated from the final liquid product in a separation zone removed from the conversion zone or reactor. The use of two zones result in increased costs for slurry hydroprocessing. Thus, there is a need for improvements in slurry reactor systems which are more efficient and essentially more economic.